10795 Lawnboy, Honda Engine, Can't start-- appears no spark

Bertrrr said:
Remove the kill wire off the coil and check for spark , if it gives you spark the problem is with the wire if not, it's the coil assembly.
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Well Bertrr, I did so, and sure enough it sparked so the wire or switch have to be bad.

Also, had to pull the flywheel to get access to the kill wire and kill switch. I found the wire fine, good continuity.
I had to disassemble the bracket assy to get at the kill switch. It is a simple micro-switch with a lever to actuate. Nice idea for a design but the switch is not enclosed and all the internals were corroding. Testing before removal showed no signs of life-- all 3 contact points tested dead to both positions of the switch arm. It appears I need to buy an entire assembly bracket with this on it; riveted to the bracket.
Will look for a new assembly.
 
schreib69 said:
kill switch. It is a simple micro-switch with a lever to actuate. Nice idea for a design but the switch is not enclosed and all the internals were corroding.
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Cover the new switch in marine grade shrink wrap. Has glue that ooozes out when you shrink it down. Seals both ends from moisture and future corrosion. This is an ultra low amperage slash voltage circuit. No issues of overheating. Just grounds the coil out when killing the key/engine.




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schreib69 said:
Interesting, you guys apparently don't use the OHMS test to check coils. . . hmmm. Maybe the reason is coil resistance is not specified ?? on many of the small engines and it is not so reliable for some reason.
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Most have a fancy circuit chip you can't test with common tools. It either sparks at low, mid and high revs or not. This ain't the space shuttle fella's.
 
slomo said:
Cover the new switch in marine grade shrink wrap. Has glue that ooozes out when you shrink it down. Seals both ends from moisture and future corrosion. This is an ultra low amperage slash voltage circuit. No issues of overheating. Just grounds the coil out when killing the key/engine.
Click to expand...
OK guys, thanks for all the info.
I solved the problem. The corroded microswitch was junk, confirmed after I physically opened it up. Probably I completely killed it when spracing in CRC cleaner and WD40 in my attempt to free up the choke lever arm. (It would not start after that bunch of squirts.)

Here is HOW:
-- Removed and trashed the kill switch.
-- wired a simple toggle switch between the kill switch wire from coil and the ground used previously by the old kill switch.
-- mounted the toggle switch on the choke bracket; up to run, Down to kill

I still use the pull back bail on the handle to actuate the choke travel and both the toggle and the rear chute sensor will still both kill the engine.
Basically, I made the controls back to the design 20 years ago; it is both safe and foolproof and won't fail due to a $2 switch made for tinker toys.
 
schreib69 said:
I can NOT get this thing re-started; can't figure what I may have done to mess it up. The other day I was not able to shut it off and finally figured that the lever arm with a spring on it is meant to pull the contact off when you release the handle-- it was stuck hard. I shot it with varioius cleaners(brake cleaner, WD40, etc ) then blow dried with compressed air. It now does a fine job of moving but I can't get the mower started to even test to see if that allows it to work as it should.

I am hoping for some troubleshooting help. Below are images and questions.
#1: I noticed elsewhere on this forum folks were looking for the electrical diagram-- me too. Any help with that?

My present conviction of the problem and background:
-- I checked for spark and got one at the plug.
-- I verified the shut off valve is pointed LEFT, giving flow to the carb; so I have fuel. It was last used for an hour and worked just fine until having to shut it down by closing that valve.
-- I have no reason to believe the plug is fouled or not gapped right, checked and it is OK; no reason to believe the choke is failing, verified;
-- I sprayed starting fluid into carb and can't even get it to cough. . . THAT is really odd being there is spark.
my conclusion is that somehow electrically it is self-killing during start but no idea how that could be.
-- I pulled the recoil unit and top cowl off and found some mouse bites on the coil wire (to the plug, at the coil) but it was obviously that way while I last used it.
View attachment 73509 View attachment 73506View attachment 73507
I can guess that maybe the micro-switch Dana Games that is closed when the handle bail is closed(see image) is damaged-- from spraying stuff on it?!@$# Who knows. If damaged the switch will not be "made" when the bail handle is closed.
Other than that I have no clue here. Hope some one here does.

thanks for reading.

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Why can't get the mower started to even test to see if that allows it to work as it should?
 
duke427 said:
Why can't get the mower started to even test to see if that allows it to work as it should?
Click to expand...
Because, if you read my solution above, I found that the KILL switch failed in the KILL position.
A cheap $2 switch, replaced with another manual toggle switch I had laying around for 20 years. Removed kill switch and all its mechanism that forced use of the stupid handle-bail requiring one to hold it while starting. Now, I only flip the switch UP to start and DOWN to kill, nothing automatic about it. Like 50 years ago designs.
 
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